/*******************************************************************************
 * Copyright (c) 2000, 2010 IBM Corporation and others.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.draw2d;

import org.eclipse.draw2d.geometry.PointList;

/**
 * Locator used to place a {@link RotatableDecoration} on a {@link Connection}.
 * The decoration can be placed at the source or target end of the connection
 * figure. The default connection implementation uses a {@link DelegatingLayout}
 * which requires locators.
 */
public class ArrowLocator extends ConnectionLocator {

	/**
	 * Constructs an ArrowLocator associated with passed connection and tip location
	 * (either {@link ConnectionLocator#SOURCE} or
	 * {@link ConnectionLocator#TARGET}).
	 *
	 * @param connection The connection associated with the locator
	 * @param location   Location of the arrow decoration
	 * @since 2.0
	 */
	public ArrowLocator(Connection connection, int location) {
		super(connection, location);
	}

	/**
	 * Relocates the passed in figure (which must be a {@link RotatableDecoration})
	 * at either the start or end of the connection.
	 *
	 * @param target The RotatableDecoration to relocate
	 */
	@Override
	public void relocate(IFigure target) {
		PointList points = getConnection().getPoints();
		RotatableDecoration arrow = (RotatableDecoration) target;
		arrow.setLocation(getLocation(points));

		if (getAlignment() == SOURCE) {
			arrow.setReferencePoint(points.getPoint(1));
		} else if (getAlignment() == TARGET) {
			arrow.setReferencePoint(points.getPoint(points.size() - 2));
		}
	}

}
